function popup(url) 
	{
		var width = screen.availWidth/2;
    	var height = screen.availHeight/2;
    	var left = (screen.availWidth-width)/2;
    	var top = (screen.availHeight-height)/2;
    
		window.open(url, 'Popup', "width=" + width + ",height=" + height + ",top="+ top +",left="+ left +",scrollbar=1,resizable=1");
	}

	function bevestig(vraag,url)
	{
		answ = confirm(vraag);
		if (answ)
			window.location=url;
	}
	
	
	
// HTML EDITOR
	
	var area;
	var showDiv;
	var formattedStr = "";
	startPosition = 0;
	var endPosition = 0;

	window.onload = function()
	{
		area = document.getElementById("area");
	};	

	function insertTag(tag)
	{
		findPositions();

		var text = area.value;
		if (startPosition!=endPosition) 
		{
			var sbStr = text.substring(startPosition,endPosition);
			sbStr = '[' + tag + ']' + sbStr + '[/' + tag + ']';
	
			fillsFormattedString(text,sbStr);
		}
	}
	
	function insertImage(element)
	{
		vraag = confirm('Adbeelding links ? druk OK\nAfbeelding rechts ? druk Annuleren');
		if(vraag)
			tag = 'afbr';
		else
			tag = 'afbl';
			
		findPositions();

		var text = area.value;
		if (startPosition!=endPosition) 
		{
			//var sbStr = text.substring(startPosition,endPosition);
			sbStr = '[' + tag + ']' + element.options[element.selectedIndex].value + '[/' + tag + ']';
	
			fillsFormattedString(text,sbStr);
		}
	}	
	
	function findPositions()
	{
		var text = area.value;

		if (document.selection) 
		{
			// Internet Explorer
			var range = document.selection.createRange();
			var dpl = range.duplicate();
			if (range.text.length > 0) 
			{
				dpl.moveToElementText(area);
				dpl.setEndPoint("EndToEnd", range);
				startPosition = dpl.text.length-range.text.length;
				endPosition = startPosition + range.text.length;
			}
		}else 
		{
			// Mozilla Firefox
			startPosition = area.selectionStart;
			endPosition = area.selectionEnd;
		}
	}

	function fillsFormattedString(text, selectedText)
	{
		// split textarea value into three pieces: before startPosition,
        // startPosition until endPosition, and after endPosition
        if(startPosition==endPosition)
        	alert('Ze zijn wel gelijk eh');
        
		var str1 = text.substring(0,startPosition);
		var str2 = text.substring(startPosition,endPosition);
		var str3 = text.substring(endPosition,text.length);

		// replace str2 with formatted substring (selectedText)
		str2 = selectedText;
		// form the new string
		formattedStr = str1+str2+str3;
		area.value = formattedStr;
	}